Detachable drill-bit.



C. SLY.

DETACHABLE DRILL BIT.

APPLICATION FILED 11111128.1915.

23, 1916. SHEET l'.

Patented M 3y 2 SHEETS- I" HHH C. SLY.Y DETACHABLE DRILL BIT.

Hen 2.

Fae. FIG. e. 'y

W//VESSES.' /VI/E/VT? @@bw/w/ Mf/ 74 MQ@ We@ v I AITIM/ver I orriicn.

I CHARLES SLY, F HOUSTON, TEXAS.

DETAGHABLE DRILL-BIT.

y Appucationmed May 2s, 1915.

I To yall whom t may concern Be it known that I, CHARLES SLY, a citizenofthe United States, residing at Houston, in the county of Harris andState of Texas, have invented certain new and useful Imrovements inwhich the following is a specification.

This invention relates to new and useful improvements in a detachabledrill bit.

The object of the invention is to provide a bit of the characterdescribed that may be attached to and detached from the lower end of adrill stem without withdrawing thc drill stem from the bore.

With the above and other objects in view, the invention has particularrelation to certain novel features of construction, operation andarrangement of parts, anl example of which is given in thisspecification, and illustrated in the accompanying drawings wherein:

Figure 1, shows a vertical sectional 4view of the bit. Fig. 2, shows avertical sectional view ofthe means for xing the bit in the drill stem.Fig. 3, shows a transverse sectional view thereof. Fig. 4, shows avertical sectional view of the device for lowering the bit into andwithdrawing it from the drill stem. Figs. 5 and 6, show views,`respectively, of the bit support taken from opposite sides. Fig. 7,shows a vertical sectional view of the pilot bit, and, Fig. 8, shows atransverse sectional view ofthe bit, taken on the line a-a of Fig. 7.

Referring now more particularly to the drawings wherein like numeralskof reference designate similar parts in each of the figures, thenumeral 1, refers to the drill stem, and the numeral 2, refers to atubular section, to which the bit proper isattached. When in operation,this section is secured within the lower end of ythe stem and projectsbelow the lower end of said stem and swedged or threaded into thelowerend of thetubular section 2, is the pilot bit 3, which may be ofany desired construction, but as shown, is in general contour of yaninverted conical' form.; lessening in diameter toward the lower end orpoint thereof, in steps, as shown, presenting abrupt annular shoulders,so that the bore will be gradually enlarged as the drilling processproceeds. Side cutters 4, 4, are provided, which play through slotsarranged in opposite sides of the tubular section 2,

and which are pivoted at'their upper ends to v said section, and whosecutting edges pro- Specicaton of Letters Patent.

Detachable Drill-Bits, of

Patented May 23, 1916.

Serial No. 30,927.

ject out through said slots. Plates 5, 5, are pivoted at their upperends immediately above said slots, on each side, which normally closethe slots against the passage of water, and flexible springs 6, 6, aresecured at their upper ends to the inside wall of the section 2, andthey converge toward each other, and their lower free ends rest againstthe inner sides of the plates 5, 5.

An Laxiallyextending shaft 7, is provided within the drill stem, to thelower end of which is ixedan' inverted conical shaped wedge 8, whichnormally rests between springs 6, 6, and hold them against the plates 5,5, which operate to force the cutters 4, 4, through their correspondingslots and hold them in extended position. Fixed in the section 2, isthedisk 9, through va central orifice in which theshaft 7, extends and acollar 10, is fixed on the shaft underneath said disk, so that'by anupward pull upon the shaft, said collar will operate to lift the entirebit and its support and elevate the samethroughsaid stem. Fixed to theshaft 7, and spacedapart ltherealong, are a plurality of cross bars 11,11, and pivoted to each of saidbars on opposite sides of the shaft, arethe levers 12, 12, to the outer sides of which are attached the blocks13, 13, which are bolted also to opposite sides of the section 2. vFixedupon said shaft and spaced apart at suitable intervals are the invertedfrusto-conical shaped wedges 14, 14, and as the shaft 7, is lowered tothe desired point, said wedges force apart the upper free ends of thelevers 12, 12. The section 2, as shown in Figs.v 5 and 6,'has triangularsections cut from opposite sides and extending approximately from end toend, so asto permit the expansion of the section. .lhen the levers 12,12, are forced apart,.the section 2, is expanded and grips the drillstem on the inside and said section 2, and the bit carried thereby, isthus fixed vrelative to the stem. The wedge 8 and wedges 14, 14, are ysolocated that the former will be iny position to force the blades 4, 4,outwardly when the latter lpa'ss'between the levers 12, 12, so as tolock the bit in position, relative to the stem, at the proper time.

For the purpose of withdrawing the bit, a cylindrical section 15, isprovided, which is of smaller diameter than the section 2, so as to passwithin the same and the upper end thereof has the bail 16, to which asuitable cable, as 17, may be attached. The upper @mi ofthe Shaft 7, hasa Coni'cai'shaped head v8, and pivoted within the section 15, toopposite sidesv thereof, are the dogs-19, 19.

When it is desired to withdraw the bit,l the section 15, is let down bythe cable 17,'until the freeends of the dogs 19, 19, clear the vlowerend of the head y18, and they will be forced under said head byineansofthe respective flat springs 20, 20, which are se? cured to 'saidsection'l, onf opposite sidesl By an upward the bit may be drawnupwardly through the stem. When it is desired to lower the bit,

the springs 20, are disengaged from the dogs 19, 19, andthe free ends ofsaid .dogs

i t engaged under the head 18, and the .device then lowered through thedrilll stem until the pilot bit 3, reaches the bottom ofthe bore. Theweight of the section 15, will carry it on downwardly, freeing the dogs19,119` fromthe head 18'. lFlat springs 21, 21, are attached to oppositesides of the section 15., and theirfree ends rest under saidl dogs, ysothaty when they are disengaged, theyl will beforced .back against thesection walls and permit the withdrawal of said section 15 from thedrill stem. The springs 20 .and 21, are soattached that they may beeasily withdrawn from operation against the dogs 19, 19, as whenone lisused the other will not be required. In replacing the drill, when. thepilot bit has reachedy the bottom of the'lbore, the wedges'S. andv 14will have again .assumed a position vbetween the springs 6, 6 and the,corresponding levers 12, 12, and will operate to lock the section 2, andthe'blades 4, 4, in the position herein before explained and the weightof the shaft 7, and theappendants thereof are sufficient to holdthe bitlocked in position.l WhatI claim is: Y

1. A device of the'character described in.

cluding a drill stem, an expansi-ble vcylindricalsection within saidstem, a bit carried by said section and means for expanding the sectionand locking the same against.move-l lment relative to the stemn -Adevice the character including adrill stem, an expansible cylindricalsection within said stem, a bit carried by y the lower end of saidsection, a plurality of side cuttersl carried thereby, means forexpanding said section and locking the same against movement relative tothe stemyand .means forlocking said side cutters in a fixed positionrelative to said sections.

3. A device ofthe character 'described ini i cluding a. drill stem, yanlexpansiblecylindrical section within saidstem, provided withslotscut-through the wallthereof, a pilot bitcarried bythe lower end ofsaidl section, cuttinglblades pivoted thereto vand adapted` Y to projectthroughsaid slots, meansfforvexpanding said section andk lockingrthe/same against movement relativeto the stem, and f meansl forfofrcingsaid side cutters topro# ject through said vslots and locking the samein said position.-

.4, A deviceof the character described in-V cluding a drill stein, anexpansible section i therein, a bit `carriedby the lower end of saidsection, means for .expanding the section and locking the same relativeto the stem, and means for withdrawing said locking means and releasingsaid section from said f stem.

therein, a bit carried by the lowerend vof said section, means forexpanding the sec- 5. VA device'of the character described tion andlocking thevsame relative to ther steml and means for elevating saidlocking: i

means and lreleasing thev section frornthe stem.

6. A device ofthe character describedinfcluding a drill stem,anexpanding section therein, abit carried by the lower v end of saidsection, means for expanding the section and locking the same relativetothel stem, a shaft arranged axially 'relative-to the stem andcontrollingsaidlocking means, andV a mechanism for elevating said kshaftandreleasingthe locking means whereby said's'ec-`rl tion is releasedfrom said stem.: Y

In testimony whereof I vhave 'signed my'v name to "thisfspeciiicationinthe `presence of- 1;

two subscribing witnesses.

.Witnessesi f J. YEAGLEY, E`. AQLIDDELL; f

Copie; of'this pfatell? may be 'obtained @v e cents eachfliy addressingthe C omm1issioneriof. Refonte,

.- CHARLES siii-riY

